Rheostat, electric heater, &amp;c.



Patented Apr. 29, |902. H. P. BALL.

RHEDSTATS, ELECTRIC HEATERS, &c.

(Application led June 27, 1898.)

2 She'ets-Sheet I.

(No Model.)

A d s w 4.

THE MORRIS PETERS co.. immun-4o., wAsnmsrroN. n. c,

No. 699,064. Patented Ap'r. 29, |902. H. P. BALL.

RHEDSTATS, ELECTRIC HEATEBS, 81.0.

(Application med June 27, 189s.)

2 Sheets-Sheet 2.

(no Model.)

THE Nonms PETERS co., PHo1c L|THo.,wAsH|NGTuN. n. c.

HENRY PRICE BALL, OF MOUNT VERNON, NEIV YORK, ASSIGNOR, BY MESNE ASSIGNMENTS, TO H. IVARD LEONARD, OF BRONXVILLE, NEW YORK.

RHEOSTAT, ELECTRIC HEATER, 80C.

'SPECIFICATION forming part of Letters Patent No. 699,064, dated April 29, 1902.

Application filed .Tune 27,1898. Serial No. 684,619. (No model.)

T all whom, t may concern:

Beit known that I, HENRY PRICE BALL, a citizen of the United States, residing at Mount Vernon, in the county of Westchester and State of New York, have invented a certain new and useful Improvement in Rheostats, Electric Heaters, and Similar Apparatus, ot' which the following is a specification.

My invention relates to rheostats, electric lo heaters, and similar apparatus in which electric energy is converted into heat; and my object is to simplify and cheapen the construction and so construct and arrange the parts whereby the steps or sections of the i 5 resistance will be separable. These separable steps or sections are independently mounted or carried bysupports adapted to be attached to or mounted upon or within a common support consisting, preferably, of a heat absorb- 2o ing or radiating body-such, for instance, as cast-iron. W`ith such construction the steps or sections of the resist-ance may be made up in uniform or standard sizes and employed for rheostats or heaters of various sizes or 2 5 capacities by employing a greater or less number, the common support, of course, being preferably arranged in various sizes.

In the accompanying drawings to avoid un-` necessary repetition I have illustrated my in- 3o vention only as applied to rheostats.

In the accompanying drawings, Figures l and 3 are plan and end views, respectively, of a rheostat having the resistance arranged in four independent or separable steps or sections. Figs. 2 and 4 are sectional views of one of the steps or sections, showing the insulation surrounding the resistance and a 'metallic or other suitable coating surrounding the insulation. Fig. 5 is a plan view of a 4o diierent form of rheostat, one suitable for use as a ield-rheostat, and in which the steps or sections are mounted radially within the common support. Fig. 6 is a central crosssection of V,the rheostat shown in Fig. 5, and

Fig. 7 is an elevation and partial sect-ion of the steps or sections employed with the rheostat ofFig. 5.

In Figs. l to 4, inclusive, the common support 2' is shown as rectangular in shape and 5o provided on the under side with a rib 3,which is provided with four tapering holes, forming sockets forl receiving the independent supports 4, which carry the steps or sections 10 of the resistance. The outer surfaces of these supports are tapered to closely t the tapering holes inthe rib 3, and thus be held in lposition solely by friction, although,if desired, set-screws or other means may be provided to hold the support-s in place and in intimate contact with the surrounding walls of the sockets. The sections or steps lO of the resistance may be arranged in various forms'or shapes and are provided with terminal wires 8. In the form shown in Fig. 2 the conductor is refiexed, while in Fig. 4 it is arranged in a straight or plain loop. The resistance 10 is surrounded by a suitable insulating material ll, which may be glass, fire-clay, terra-cotta, or any similar or other suitable material applied in any suitable or well-known manner. In practice I prefer to surround the coating of insulation with a metallic jacket 9. This jacket is preferably made of metal and maybe made in suitable form to receive the insulated resistance; but as a matter of cheapness and to facilitate construction I prefer to cast about the insulating material a low-fusing metal, such as lead, white-metal, or similar material. The advantage of the latter arrangement is that the common support 2 may be made of any desired -material or metal, such as casti'ron or brass or other high-fusing metal in commercial use, while the jackets 9 can be made of any suitable low-fusing metal which will not disintegrate the insulating-coating ll. Furthermore, the jacket so formed can be readily worked or shaped into form to ac eurately iit the sockets in the rib 8. The terminals 8 of the independent sections are adapted to be connected to binding-posts l2 on the under side of the common support 2, and which binding-posts are suitably insulated from said support and connected to contact-buttons I on the upper side of the support, as is well understood. The first or righthand contact-button l is connected linderneath the support tothe binding-post 6, and the other binding-postv 6 is connected tothe pivoted contact-blade 5', which is arranged to make contact with the button 1, a handle 7 being provided to operate the contact-blade. As shown, the terminals 8 have a larger cur- ISO rent-carrying capacity than the heating-cond uctor l0. By forming the joint between the two within the insulating material the heat developed outside of the insulating material is kept sufficiently low to prevent deterioration. If, however, this joint were exterior of the insulating material, the heat developed in the conductor would rapidly destroy it, owing tothe relatively low heat-radiating capacity of the air.

In Figs. 5 and the common support 2 is circular in form, having a heavy rim in which is formed a series of tapering holes to receive the steps or sections et, as in the arrangement of Fig. l. In this arrangement the terminal wires S of adjacent sections are shown as connected together; but it will be understood that, if desired, binding-posts l2 maybe provided, as in the arrangement of Fig. l. Also in this arrangement the contact-blade 5 is connected with one of the binding-posts (5, the other binding-post (3 being connected to one of the terminal wires S of the last section.

The section of resistance illustrated in Fig. 7 comprises a support 14, which may be of insulating material or of metal coated with an insulating material. A conductor l() is wound on this support and covered with a layer of insulation I3. As shown, the resistance is wound on the core or'support in a double spiral, one end being connected tothe contact-button l, which is secured to the core lhand insulated therefrom if the core is made of metal, and the free ends or terminals S of the resistance lO pass out through suitable holes at the inner end of the core for connection to adjacent sections, as shown in Figs. 5 and 6. The support shown in Fig. 7 may be inserted in the sockets ofthe common support in the form shown, or, if desired, a coating of metal may be applied thereto either before or after insertion in the sockets.

In both forms of rheostat shown the individual supports 4E may be held in place by pouring molten metal into the sockets while the supports are held therein, so that upon cooling the metal will rigidly attach the individual supports to the common support; but I prefer, however, to arrange the individual supports so that they may be readily removed from the common support when necessary.

In the constructions shown it will be seen that practically the entire length of each section of the resistance lies in close proximity to the metal or other material of the common support, whereby the heat energy developed in the sections of the resistance will be rapidly transmitted to the surrounding material of the common support.

l. As a new manufacture, a unit resistance for a device wherein electric energy is intentionally converted into heat, comprising a supporting-body of'mineral insulating material, a conductor embedded therein, and a metal protector Afor the insulating material adhesively engaging the same, substantially as and for the purposes set forth.

2. As a new manufacture, a unit resistance for a device wherein electric energy is intentionally converted into heat, comprising a supporting-bodyof vitreous insulating material, a conductor embedded therein, and a metal protector for the insulating material adhesivelf,T engaging the same, substantially as and for the purposes set forth.

As a new article of manufacture, a unit resistance for a device wherein electric energy is intentionally converted into heat, comprising a layer of mineral insulating material, a conductorembedded therein, a terminal having a larger currentcarrying capacity than the conductor, connected to the conductor and having the joint located within the insulating material, a protective and heat-conducting metallic case, and a metallic support adapted to receive a series of said unit resistances with their metallic cases in close mechanical contact therewith.

4t. As a new article of manufacture, a unit resistance for a device wherein electric energ f is intentionally converted into heat, comprising a layer of vitreous insulating material, a conductorembeddedtherein, a terminal having a larger current-carrying capacity than the conductor, connected to the conductor and having the joint located within the insulating material, a protective and heat-conducting metallic case, and a metallic support adapted to receive a series of said unit resistances with their metallic cases in close mechanical contact therewith.

5. As a new article of manufacture, a unit resistance 'for a device wherein electric energy is intentionally converted into heat, comprising a layer of glass, a conductor embedded therein, a terminal having a larger currentcarrying capacity than the conductolgeonnected to the conductor and having the joint located within the layer of glass, a protective and heat-conducting metallic case, anda metallic support adapted to receive a series of said unit resistances with their metallic cases in close mechanical contact therewith.

U. In an apparatus wherein electric energy is intentionally converted into heat, the combination of a heat-absorbing support having a series of tapered openings therein, and a unit resistance engaging each of said openings by friction and comprising an insulatingcore, a conductor embedded in said core, and a metal jacket surrounding the core, substantially as set forth.

7. In an apparatus wherein electric energy is intentionally converted into heat, the combination of a heat-absorbing support having a series of tapered openings therein, and a unit resistance engaging each of said openings by friction and comprising an insulatingcore, a conductorembedded in said core, and a soft-metal jacket surrounding the core, substantially as set forth.

IOO

IIO

S. In an apparatus wherein electric energy is intentionally converted into heat, the combination of a heat-absorbing support having a series of tapered openings therein, and a unit resistance engaging each of said openings by friction, and comprising a core of mineral insulating material, a conductor embedded in said core, .and a protective and heat-conducting metallic case.

9. In an apparatus wherein electric energy is intentionally converted into heat, the combination of a heat-absorbing support having a series of tapered openings therein, and a unit resistance engaging each of said openings by friction, and comprising avcore 'of vitreous insulating material, a conductor embedded in said core, and a protective and heat-conducting metallic case.

10. In an apparatus wherein electric energy is intentionally converted into heat, the combinationot` aheat-absorbingsupport having a series of tapered openings therein, and a unit resistance engaging each of said openings by friction, and comprising a core of glass, a conductor embedded in said core, and a protective and heatconducting metallic case.

l1. In an apparatus wherein electric energy is intentionally converted into heat, the combination of a heat-absorbing support havinga series of tapered openings therein, and a unit resistance engaging each ofl said openings by friction, and comprising a core of mineral insulating material, a conductor embedded in said core, a terminal having a larger current-carrying capacity than the conductor connected to the conductor and having the joint located Within-the core, and a protective and heat-conducting insulatingcase.

This specification signed and witnessed this 25th day of June, 1898.

HENRY PRICE BALL.

Vitnesses:

ARCHIE G. REEsE, J No. R. TAYLOR. 

